Three missionaries and three cannibals must cross a river using a boat which can carry at most two people. If cannibals ever outnumber missionaries on either bank, the missionaries will be eaten. How do they all get across?
Common Wrong Answers
“All missionaries cross first”
If all missionaries cross first, the cannibals left behind on the initial bank will outnumber the missionaries, leading to their consumption.
“Send one missionary and one cannibal at a time”
Sending one missionary and one cannibal at a time does not effectively manage the risk of cannibals outnumbering missionaries on either bank, especially when the boat returns.
“Cross with two missionaries and one cannibal”
This option would leave one cannibal behind with two missionaries, which means the cannibal would outnumber the missionaries on that bank, putting them at risk.
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